Jonah newton



J. NEWTON.

SAW TOOTH. I

No 94,022 Patented Aug. 24, 1869.

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6a v I f K JONAH NEWTON, OF NEW Y ORK,.N. Y.

Letters Patent No. 94,022,'dated August 24,

IMPROVEMENT IN SAW-TEETH.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern.-

Be it known that I, JONAK Nnwrox, of the city, county, and State of New York, have invented a new and useful Improvement in Removable Saw-Teeth; and I do hereby declare that the following is a full, clear, and exact'description thereof, which will enable others skilled in the art to make and use the same, reference being bad to the accompanying drawing, forming part of this specification.

This invention relates to improvements in the arrangement of removable saw-teeth, and the means of holding. them in the saw-plate, calculated to provide a ready means of inserting, removing, or adjusting them, and of holdingthem in the required positions,

by the frictional action of springs, arranged to be capa- M bio of imparting the requiredamount of friction with- Similar letters of reference indicatev corresponding parts.

My invention contemplates the employment of teeth, A, of greater or less length, asrequired', representing segments of true circles, or nearly so, to be secured in recesses in the saw, having correspondingforrn, as far as the teeth extend, by springs B, the teeth being grooved on the back, as represented at O, to receive corresponding projections D of the saw-plate.

This form of teeth I find most preferable to use, for' the reason that they aflord a greater surface for the frictional contact of the springs than straightteeth with the same depth of recessing the plates, and are quite as easy to adjust, and cheap to make.

As it is highly desirable to hold the teeth so that they cannot be started from tbeir positions by the greatest resistance of the timber upon the points they may be subjected to in sawing, without producing sufiicient strain to warp or buckle the plates, it becomes important to produce the greatest possible amount of friction with the least amount of strain.

To this end, I form on the concave edges of the teeth a deep groove, E, with oblique sides, and fit thereto a corresponding tongue, F, on the convex: edge of the spring, so shaped'as to wedge into the groove, with its side walls fairly fitting the side walls of the groove. In this manner, with the base G of. the spring fitting in the-opposite side of the recess in the saw-plate, and

the pointH pressing against the teeth, the latter will be held with so littlepressure of the spring as not to endanger the warping of thesaw-plate. To add to the capacity of the spring, I propose also, if required, I

to make grooves of similar form at the, other edge of the teeth, and similar tongues on-the saw-plate.

But I consider a more preferable means of accomplishing the same to be, the introduction of bolsters or extension-plates I, at the bottom of the teeth, and

this I propose to adopt.

' These bolsters will be grooved similarly to the teeth, and receive the projections of the plate and the springs,

mer'ely' furnishing extensions of the groove E, into which the tongue nor the spring may be forced.

The springing-movement of the point 11 of the spring is adj nsted so as to permit the removal of the pressure of the tooth by a slight withdrawal of the spring in'the opposite direction, and this I accomplish in the following manner:

Between the points G G of the spring a space is .provided, between the base of'the spring and .the wall of the recess in the plate, and opposite thereto, at M, the plate of the spring is recessed, or slotted, to remove suflicient metal to permit it to spring between the said points G G; and for springing it l providea straining-implement, composed of a stock, N, having a pin, 0, projecting from one side, near one end, to take into the slot 'M,-and a turning-pin, P, passing through the other end of the stock, the said pin being I provided with ahandle, Q, at one end, and a stud at' the other, to take into'holes made in the. saw-plate,

the said stud being eccentric to the journal of the turning-pin in the stock.

The holes being adjusted at the proper distance from the slots M of the springs, the latter may be readily sprung back into the space between points G G, bythe turning of the said pin P when, the stud O is eng' ged in the slot M and the other stud in the proper hole in the saw-plate.

When the springs are so contracted, I take a metallic pin, or other suitable instrument, and engage one end with the holes It in the teeth or extensionplates, to move them more readily either way, as required.

By the employment of these exter'lsiomplates, or

bolsters, I may, if preferred,exte'nd the friction-grooves E and the corresponding wedging-projections F a halfcircle, or more and .tlrereby secure the teetlrwith a very light sprrng, S, as represented in modification shown in fig. 3, the strain: of which would bevery much less than springs bearing upon the: teeth only.

and thereforebetter adapted for thin and weak plates. These springs may be retracted by other and simpler means.

In case no bolster or extension-plate is used, I prefer to adopt the form of spring represented in fig. 2.

Having thus described my invention,

What Lclaim as new, and desire to secure by Letters Patent, is-

1. Thecombination of the segmental tooth A and holding-spring B or S with a. circular recess ofa'sawplate or disk, either with or without the bolsters I,

all constructed and arranged substantially as herein shown and described;

2. The improved spring-retracting instrument, constructed and operating substantially as above described. v

The above specification of my invention signed by me, this 3d day of April, 1869.

' J ONAH NEWTON. Witnesses:

F. BLOCKLEY, E. GREENECOLLINS. 

